Process of making sulphuric acid esters of unsaturated alcohols



Patent cd. Apr. 6, 1937 UNITED STATES PATENT OFFICE PROCESS OF MAKING SULPHURIC ACID ESTERS OF UNSATURATED ALCOHOLS Ohio No Drawing. Application January 18, 1936, Serial No. 59,789

13 Claims.

This invention relates to a process for making products having good wetting, sudsing, emulsifying and detergent properties, consisting essentially of metal salts of the sulphuric esters of higher unsaturated alcohols by the direct union of such alcohols with a reagent consisting of the reaction products of sulphur trioxide on metal chlorides or the reaction products of chlorsulphonic acids on metal chlorides or sulphates.

Its object is to provide a practical, convenient and economical process for the making of such products.

This application is a continuation in part of our Patent No. 2,049,670, issued August 4, 1936, and is related to our copending application Serial Number 59,790, filed January 18, 1936. Application 59,790 relates to the use of a dry solid sulphonating or sulphating reagent to convert higher alcohols to the salts of the sulphated higher alcohols in a single reaction. Higher alcohols in general are covered. The present application is directed specifically to the production of salts of sulphuric esters of higher unsaturated alcohols only.

It is already well known that higher alcohols, both saturated and unsaturated, can be converted into salts of their sulphate esters having wetting, sudsing, emulsifying and detergent properties by treating them with sulphating agents such as concentrated sulphuric acid, chlorsulphonic acid, etc., under suitable condi- 'tions to form the sulphuric esters, and neutralizing the products with oxides, hydroxides, or carbonates of the metals. The products thus made from saturated higher alcohols have very satisfactory detergent properties, but those made from the corresponding unsaturated alcohols by the same methods have very inferior detergent properties, and are unsuitable for actual laundry use. It has been found, however, that if the unsaturated alcohols are treated with the sulphating agents above mentioned in a solvent such as ether of pyridine or certain other tertiary amines, the unsaturated alcohols are then converted to sulphate esters which when neutralized have detergent properties much superior to those produced without the use of such solvents. These procedures have been disclosed in an article by Gruen and Wirth (Berichte, 1922, page 2209), and in British Patent 391,435, April 21, 1933. These procedures, however, add greatly to the cost of making such products because of the additional reagents used and the additional equipment required for handling same. No method has been described heretofore, as

far as we are aware, for making sulphated unsaturated alcohol detergents of good eificiency, comparable to the corresponding saturated products, without the use of a solvent, and suitable for practical laundry use. Hence, any means that would permit the conversion of these unsaturated higher alcohols into salts of sulphated alcohols or alkyl sulphates having wetting and detergent properties comparable to those of the corresponding saturated alcohols without the use of expensive additional reagents and equipment would be very advantageous. These products made from the unsaturated higher alcohols without saturation of the double bond have certain advantages over the corresponding saturated products in that they not only have at least equal wetting, sudsing, emulsifying, and detergent properties, but they are much more soluble than the corresponding saturated products.

We have found that when the higher unsaturated alcohols are treated with the sulphating agents described below, there is produced a wetting and detergent agent in good yield having the desired properties, and much superior to the corresponding products obtained by any sulphating procedure hereto practiced without the use of solvents.

The reagent which we use may be produced as follows: I

Q a. By causing sulphur trioxide to react with a metal chloride, such as sodium chloride, potassium chloride, barium chloride, ammonium chloride, etc., or

b. By causing chlorsulphonic acid to react with either the chloride or sulphate of a metal, such as sodium, potassium, ammonium, cobalt, manganese, etc.

The reagents prepared in these two procedures are probably not identical in composition, but they act in the same manner in our process of sulphating the higher unsaturated alcohols. The reagent obtained in the first procedure is believed to consist mainly of the chlorpyrosulphonate of the metal, although according to Traube some chlorsulphonate is formed as an intermediate product. (See Traube in Berichte 1913, vol. 46, page 2513.) That obtained by the second procedure probably consists largely of the chlorsulphonate of the metal. In any event the actual composition need not be definitely established because both products react in substantially the same manner in our process. The preparation of these reagents is not a part of our invention.

While our reaction takes place with any of the unsaturated aliphatic alcohols, in producing wetting, sudsing, emulsifying and detergent agents of improved quality those primary aliphatic unsaturated alcohols containing from about twelve to twenty-two carbon atoms per molecule are to be preferred. They may either beused singly or inrnixtures, or may be mixed with saturated higher alcohols to a greater or less extent. Unsaturated higher alcohols. suitable for making good wetting, sudsing, emulsifying and detergent products by means of our process may be obtained, forexample, by saponificationof sperm oil, or by treatment of the methyl esters of unsaturated fatty acids with metallic sodium.

Ordinary sulphating or sulphonating agents such as concentrated sulphuric acid, fuming sulphuric acid, and chlorsulphonic acid, do not yield good wetting and detergent agents with unsaturated alcohols because they react with the unsaturated alcohol both at the hydroxyl group and at the double bond. In the former case the sulphuric ester results while in the latter case the double bond is saturated by the addition of a sulphonic acid grouping or in other ways. As a matter of fact, both reactions occur simultaneouslyand unavoidably when treating the higher unsaturated alcohols with these reagents, and such products have inferior properties to those made by our process, as is set forth more fully below.

The action of our reagents with the higher unsaturated primary alcohols, however, is of a definitely selective nature and takes place almost exclusively with the hydroxyl group of the alcohol and but very little with the double bond. This is an important point of difference as compared with the more common sulphating agents such as those mentioned. The presence of sulphonate groups with the ester groupings appears to invariably give products of relatively poor detergent properties, whereas if the alcohol reacts only at the hydroxyl group to produce the sulphuric ester, leaving the double bond unattacked, the result is a product having excellent detergent properties. This is accomplished by the use of our improved process, and appears to be due to the milder action of the sulphating agents which we employ. Furthermore, our process converts a higher percentage of the alcohol to ester than ordinary sulphation procedures, thus leaving less unsulphated alcohol in the product, which is believed to be another reason for the improved properties of our product.

In preparing our reagent with the use of sulphur trioxide and sodium chloride, or other metal chloride, we pass the sulphur trioxide gas 7 into an acid resistant chamber containing pulverized sodium chloride, and agitate the mixture, while cooling same to prevent the temperature from rising higher than about 30 C. The product is a solid in powder form.

In preparing our reagent with chlorsulphonic acid we mix the commercial chlorsulphonic acid with the sodium /chloride or sulphate or corresponding salt of other metal at room temperature. A vigorous reaction ensues with a rise of temperature, and evolution of hydrochloric acid gas when chlorides are used. The temperature is preferably kept below about 50 C., as side reactions take place at higher temperatures with evolution of chlorine in some cases.

In making these reagents by either procedure, moisture must be excluded as moisture decomposes them.

An excess of the dry salt (NaCl, Nazsol, etc.) in preparing the reagent by either procedure is desirable in the reagent as used, as it makes a more friable reaction mixture which is more easily mixed and ground. The excess may conveniently be from twenty-five per cent to one hundred per cent of the calculated quantity.

Our reaction with the alcohols is carried out by adding the powdered reagent, prepared by either procedure above described, to the unsaturated alcohol in a liquid condition in a suitable acid resistant vessel at a temperature of about 30? C. and stirring for about an hour or until the reaction ceases. The temperature rises, but should preferably be held below about 50 to 60 C. until the reaction is completed. Evolution of hydrochloric acid gas occurs. We preferably use an excess of the reagent amounting to one fourth to one half more than the theoretically calculated quantity in order to secure rapid and complete action. At least ninety per cent of the alcohol is converted to the sulphate ester under these conditions, and usually ninety-five or ninety-six per cent.

This reaction may be carried out in the presence of an inert. liquid medium if desired, in which the materials can be dissolved or suspended and thereby kept in intimate contact. Carbon tetrachloride and various other chlorinated hydrocarbons such as dichlorethane and anhydrous other may be used for this purpose. In general, however, we prefer to carry out our process without the use of a liquid medium.

The reactions may be represented as follows, assuming that the SOa-NaCl reaction product is mainly the chlorpyrosulphonate, and the HClSOa-NaCl reaction product is mainly the chlorsulphonate, and R being the alkyl radical of an alcohol.

(1) ROH NaClSO; RNBSO4 H0] (Alcohol) (Sodium (Sodium chlorsulalkyl phonate) sulphate) (2) ROE NaCl(SOa)z RNaSO; RHSO| +1101 (Alcohol) (Sodium (Sodium (Alkyl pyrochloralkyl sulphusulphonate) sulphate) ric acid) (3) RHSOl NaCl RNaSO; HCl

(Alkyl (Excess (Sodium sulphuric salt) alkyl acid) sulphate) Reaction (3) appears to be incomplete so that some RHSO4 remains in the mixture after reacting, together with some of the evolved HCl, and these compounds together with any excess of reagent used are subsequently neutralized by mixing with a finely ground metal oxide, hydroxide or carbonate in sufficient quantity to neutralize any acidity in the mixture, thus obtaining a solid product which is found to have excellent wetting, sudsing, emulsifying and detergent properties without further purification. Usually the same metal would be selected for neutralizing excess acid as was used'in the reagent. The neutralized excess reagent may be allowed to remain in the neutralized product as it is harmless for ordinary uses, or it may be removed by a purification process as described below. The product, however, would be unstable unless neutralized or made slightly alkaline. The amount of neutralizing agent required is much less, however, than when the alcohol is sulphated with chlorsulphonic acid, for example, in the usual manner.

Ifa purer form of product is desired it may be treated with petroleum ether or other suitable organic solvent to remove unsulphated organic material; it may also be purified, either with or without previous treatment with petroleum ether, by dissolving the material in ethyl alcohol or other suitable organic solvent for the saltof the sulphated alcohol, filtering from inorganic and other impurities, and the solvent then removed by evaporation. v I

The selective action of our reagents on the hydroxyl group of the unsaturated alcohols without seriously attacking the double bond, or with minimum action on same, as compared with the action of ordinary sulphating agents on the same alcohols is clearly shown in the following experiment.

Alcohols from sperm oil, mainly unsaturated. and consisting mainly of oleyl alcohol, were sulphated and neutralized by our procedure, and another portion was sulphated by the usual sulphating procedure using chlorsulphonic acid with subsequent neutralization with sodium carbonate. The sodium salts thus obtained in each case were boiled with dilute aqueous hydrochloric acid for several hours in order to hydrolyze the sulphuric esters and regain thefree alcohols. The alcohols thus set free were then compared with the original alcohol before sulphation with the following results:

' Iodine Acid Sap. Hydroxyl Alcohol val. val. val. val.

Original 86. 5 0. l 0. 6 209 After treatment with our reagents,

and hydrolyzed 79. 2 6 5. 8 195 After treatment with chlorsulphonic acid and hydrolyzed 54. 4 3. 7 13. 5 214 Each of the figures on treated alcohols in the above table is an average of figures from three separate treatments. Inspection of these results shows that with the ordinary chlorsulphonic acid treatment the iodine value was reduced by about 32 points due to saturation of the double bond by thesulphating reagent while with our reagent the iodine value was reduced only about 7 points. Likewise, the acid value and the saponification value of the recovered alcohols are much higher when treated by the ordinary process than by our process, which result we believe is due to a partial greatly superior in detergent properties to those obtained by the ordinary procedure.

The following examples will illustrate our process in greater detail.

Example 1 Alcohols from sperm oil, substantially unsaturated, having an iodine value of 86, hydroxyl value 209 and average molecular weight of about 270, were used. 2'70 parts of the alcohol were mixed with 180 parts of our reagent made by reacting sulphur trioxide with sodium chloride, and containing about 50 parts of excess sodium chloride, in an acid resisting vessel until the reaction was complete. Care was taken to protect the materials from moisture. After testing for free acidity in the product a slight excess of dry sodium carbonate was thoroughly mixed in to neutralize any acidity due to the excess of reagent. The neutralized mixture when dissolved in water had excellent wetting, sudsing and detergent properties, which were much superior to those of a similar product prepared by the best known sulphating procedures using chlorsulphonic acid and neutralizing the product, and entirely suitable for practical laundry use.

Example 2 The product of Example 1 was extracted with petroleum ether to remove organic impurities and then dissolved in ethyl alcohol, filtered, and crystallized by evaporation of the ethyl alcohol. The product was a white, solid powder having very superior 'wetting, sudsing, and detergent properties, even better than those of the well known sodiumlauryl sulphate.

' Example 3 The product of Example 1 before neutralizing with sodium carbonate was mixed with 500 parts of water containing a slight excess of caustic soda over that required for neutralization of excess acidity. This formed a pasty mass which, without further purification, can be used for ordinary commercial use as a wetting, sudsing, emulsifying and detergent agent.

This paste may also be dried by passing over hot rolls or by spraying in the known manner.

Example 4 The mixed alcohols obtainable from whale oil by sodium reduction of the methyl esters of the fatty acids by the well known method of Bouvault and Blane, having an iodine value of 108, hydroxyl value of 220, and molecular weight of 255, were used in this example. 255 parts of the mixed alcohols were treated with 300 parts of the reagent made by reacting chlorsulphonic acid with sodium sulphate in the same way as described in Example 1. of this example had excellent wetting, sudsing, emulsifying and detergent properties, much superior to those of a similar product obtained by sulphating with chlorsulphonic acid and subsequent neutralization, and suitable for practical laundry use. It will be noted that the alcohols used were not pure unsaturated alcohols, but mixed alcohols containing some saturated alcohols, but the effect of the new procedure on the unsaturated alcohols was sufiiciently marked to make a decided improvement in the properties of the mixed product as compared with a similar product sulphated by previously known methods. In any of the above examples other metals than sodium could be used, provided they form sufiiciently soluble salts with the sulphuric esters of the unsaturated alcohols, such as potassium, ammonium, barium, cobalt, manganese, etc.

Comparative detergency tests were made by a standardized procedure, using water of moderate hardness (such as 21 grains per gallon for example) and simulating actual laundry conditions as far as possible. These invariably showed that the unsaturated alcohol sulphates prepared by our process removed a given amount of soil from a standard soiled fabric with the use of much less of the detergent than when the unsaturated alcohol sulphates were prepared from the same alcohols with chlorsulphonic acid in the usual way. The figures ranged from about .03 per cent to .06 per cent of our product as compared with .16 per cent to .30 per cent of the usual product to obtain the same result. These figures show clearly the improvement obtained by our process, which is a very important difference and makes our product of practical utility comparable to The neutralized product other sulphated alcohol detergents such as the sodium lauryl sulphate for example, while the unsaturated alcohol sulphates prepared by the usual sulphating procedures have little practical 5 use as detergents.

The advantages of this new procedure are that the primary unsaturated higher alcohols are entirely or mostly converted directly to salts of the sulphuric esters in a single operation, instead of first making the sulphuric ester and in a second operation neutralizing the ester, as in prior practice; the double bonds of the unsaturated alcohols remain substantially unattacked; no solvent is used; the result is a product of very superior wetting, sudsing, emulsifying and detergent properties, suitable for practical laundry use, and a considerably reduced cost of operation.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:-

I. A process for preparing wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting unsaturated aliphatic alcohols containing from twelve to twentytwo carbon atoms per molecule with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a metal chloride and the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, said metal being one which forms a water-soluble product with the sulphuric ester of said alcohol.

2. The process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use consisting essentially of water soluble salts of the sulphuric esters of unsaturated aliphatic alcohols containing from about twelve to twenty-two carbon atoms per molecule with substantially no sulphonation of ,,the double bond of said alcohols, comprising reacting said alcohols with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a metal chloride and the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, said metal being one which forms water-soluhle compounds with the sulphuric esters of said alcohols.

3. The process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use consisting essentially of water-soluble salts of the sulphuric esters of unsaturated aliphatic alcohols containing from about twelve to twenty-two carbon atoms per molecule with substantially no sulfonation of the double bond of said alcohols, comprising reacting said alcohols with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a metal chloride and the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, and treating the product thus produced with a neutralizing agent selected from the group of metal oxides, hydroxides and carbonates, said metals being ones which form water-soluble compounds with the sulphuric esters of said alcohols.

4. A process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use consisting essentially of the watersoli'ible salts of the sulphuric esters of unsaturated aliphatic alcohols containing from about twelve to twenty-two carbon atoms per molecule, comprising reacting said alcohols with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a metal chloride and the reaction product of chlorsulphonic acid soluble salts of the sulphuric esters of unsaturated aliphatic alcohols containing from about twelve to twenty-two carbon atoms per molecule, comprising reacting said alcohols with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a metal chloride and the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, the product thus obtained being treated with a neutralizing agent selected from the group consisting of metal oxide, hydroxide and carbonate, said metals, being ones forming watersoluble compounds with said product, said neutralized product being purified by dissolving the active ingredient in ethyl alcohol, separating from inorganic matter and other impurities and removing the alcohol by evaporation.

6. A process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting the alcohols obtainable from sperm oil with a reagent selected from the group consisting of the reaction product of sulphur trioxide on sodium chloride and the reaction product of chlorsulphonic acid on a sodium salt of the group consisting of chloride and sulphate, and subjecting the product of this reaction to a neutralizing agent selected from the group consisting of sodium oxide, hydroxide or carbonate.

7. A process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting the alcohols derived from whale oil with a reagent selected from the group consisting of the reaction product of sulphur trioxide on sodium chloride and the reaction product of chlorsulphonic acid on a sodium salt of the group consisting of chloride and sulphate, and subjecting the product of this reaction to a neutralizing agent selected from the group consisting of sodium oxide, hydroxide and carbonate.

8. A process for preparing good wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting oleyl alcohol with a reagent selected from the group consisting of the reaction product of sulphur trioxide on sodium chloride and the reaction product of chlorsulphonic acid on a sodium salt of the group consisting of chloride and sulphate, and subjecting the product of this reaction to a neutralizing agent selected from the group consisting of sodium oxide, hydroxide and carbonate.

9. A process for preparing wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting unsaturated aliphatic alcohols containing from twelve to twenty-two carbon atoms per molecule with the reaction product of sulphur trioxide on a metal chloride, said metal being one which forms a water-soluble product with the sulphuric ester of said alcohol.

10. A process for preparing wetting, sudsing, emulsifying and detergent agents suitable for laundry use comprising reacting unsaturated aliphatic alcohols containing from twelve to twentytwo carbon atoms per molecule with the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, said metal being one which forms a watersoluble product with the sulphuric ester of said alcohol. I

11. The process of making a wetting, sudsin emulsifying and detergent agent, which comprises causing unsaturated aliphatic alcohols characterized by the presence of molecules having from twelve to twenty-two carbon atoms each, to react with the reaction product of sulphur trioxide on a metal chloride, said metal being onewhioh forms water-soluble products of said alcohols in said reaction.

12. The process of making a wetting, sudsing, emulsifying and detergent agent, which comprises causing unsaturated aliphatic alcohols characterized by the presence of molecules having from'twelve to twenty-two carbon atoms each, to react with the reaction product oi. chlorsulphonic acid on a metal salt of the group consisting of chloride and sulphate, said metal being one wihch forms water-soluble products of said alcohols in said reaction.

13. A process for preparing good wetting, sudsing, emplsifying and detergent agents suitable for laundry use consisting essentially of the water-soluble salts of the sulphuric esters of unsaturated aliphatic alcohols containing from about twelve to twenty-two carbon atoms per molecule, comprising reacting said alcohols with a reagent selected from the group consisting of the reaction product of sulphur trioxide on a ,metal chloride and the reaction product of chlorsulphonic acid on a metal salt of the group consisting of chloride or sulphate, the product thus obtained being treated with a neutralizing agent selected from the group consisting of metal oxide, hydroxide and carbonate, said metals being ones forming water-soluble compounds with said product, said neutralized product being purified by treatment with a solvent capable of dissolving the salt of the sulphated alcohol, without dissolving substantial quantities of the inorganic and other impurities, separating from inorganic matter and other impurities and removing the solvent by evaporation.

ARNON O. SNODDY. WILFRED S. MARTIN. 

